Spinal plate

ABSTRACT

Spinal plates with additional features to improve the stability of the interface between the plate and the underlying bone. A bone plate may include one or more sharp ridges along the periphery of its underside. When attached to bone, the ridge digs into the bone and increases stability. A bone plate may alternatively or additionally include one or more holes for optional spikes, which may be inserted once the plate is attached to the bone. By separating the spikes and including them as an optional component, the plate may enhance stability while reducing or eliminating the chance of the spike injuring the patient. Furthermore, bone screws may incorporate alternating notches and ridges into the head of the screw. The notches and ridges may interface with a set screw, thereby preventing rotation and loosening of the screw.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 13/439,981, filed on Apr. 5, 2012, which is acontinuation-in-part application of U.S. patent application Ser. No.13/226,092, filed on Sep. 6, 2011, each of which is incorporated byreference herein in its entirety.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The disclosure relates to devices for immobilizing two or more vertebraerelative to one another to promote fusion of the vertebrae. The devicesand improvements described herein may also be used with other types ofbone plates or instrumentation.

2. Related Art

Adjacent vertebrae may be surgically joined together in a fusionprocedure. The procedure may join two (bi-level) or more (multi-level)vertebrae. During the surgery, the vertebrae are fixed in positionrelative to one another with a plate or other instrumentation, and abone graft is placed between the vertebrae. The bone graft will promotenew bone growth between the vertebrae, and eventually the bones willgrow together, which typically takes 6-18 months after the surgery.

More commonly, fusion of vertebrae is used as part of a treatment for aherniated disc, rheumatoid arthritis, infection, tumor, or othercondition resulting in spinal deformities. In each case, the primarydisease is treated before the fusion procedure. In the case of aherniated disc or degenerative disc disorder, for example, theintervertebral disc is removed (a procedure known as a discectomy).After the discectomy, the instrumentation is attached to the vertebrae.The two related procedures are typically performed as part of the samesurgery, to minimize trauma and expense to the patient.

Many devices are available for instrumentation of the spine in a fusionprocedure. Current spinal plates, however, suffer from one or morelimitations. For example, there are often situations and sizerestrictions that limit the number of screws that can be used in adesign or surgery. Fewer screws results in lower stability of the plate.

One solution to this problem has been to add spikes or other sharpfeatures to the plate. The spikes increase the stability of thebone-plate interface, as well as the stability of the underlying bonestructures. There is a risk, however, that the sharp features maypuncture or damage blood vessels, nerves, or other delicate anatomicalstructures during placement. There is also a difficulty for the surgeonto determine how well the plate will rest on the bone surface withoutfirst inserting the spikes into the bone.

Spinal plates are commonly fixed to bone with bone screws. Many modernplate designs incorporate blocking set screws, which prevent the bonescrews from backing out of the bone after they have been implanted.Blocking set screws, however, do not prevent the bone screws fromrotating. It is possible for the bone screws to rotate and loosen whilethey are held in place by the set screws. Loose bone screws reduce thestability of the bone-plate interface, thereby reducing the chance of asuccessful fusion procedure.

Accordingly, there is a need for a bone plate that provides enhancedstability and prevents rotation of the bone screws holding the plate tothe bone.

SUMMARY OF THE DISCLOSURE

The disclosure meets the foregoing need and allows increased safetyand/or stability using advanced bone plates, which results in asignificant increase in positive patient outcomes and other advantagesapparent from the discussion herein.

Various systems, devices and methods are provided that relate tovertebral fusion. In some embodiments, a surgical method comprisesinserting a spacer body into a disc space; operably connecting a guidemember to the spacer body; passing a plate over the guide member toposition the plate adjacent the spacer body, wherein the plate includesat least one hole to receive a fastener; and securing the plate to avertebral body by inserting at least one fastener through the at leastone hole of the plate into the vertebral body.

In some embodiments, a surgical method comprises inserting a spacer bodyinto a disc space; operably connecting a guide member to the spacerbody, wherein the guide member comprises a first portion and a secondportion, the second portion being more flexible than the first portion;passing a plate over the guide member to position the plate adjacent thespacer body; and securing the plate to a vertebral body.

In some embodiments, a surgical method comprises inserting a spacer bodyinto a disc space, wherein the spacer body includes a recess; operablyconnecting a guide member adjacent to the spacer body; passing a plateover the guide member to position the plate adjacent the spacer body;and securing the plate to a vertebral body.

Additional features, advantages, and aspects of the disclosure may beset forth or apparent from consideration of the following detaileddescription, drawings, and claims. Moreover, it is to be understood thatboth the foregoing summary of the disclosure and the following detaileddescription are exemplary and intended to provide further explanationwithout limiting the scope of the disclosure as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure, are incorporated in and constitute apart of this specification, illustrate aspects of the disclosure andtogether with the detailed description serve to explain the principlesof the disclosure. No attempt is made to show structural details of thedisclosure in more detail than may be necessary for a fundamentalunderstanding of the disclosure and the various ways in which it may bepracticed. In the drawings:

FIG. 1A shows a perspective view of an underside of a bone plate with aridge that is flush with the sides of the bone plate;

FIG. 1B shows a top-view of the bone plate of FIG. 1A;

FIG. 2A shows a perspective view of a bone plate with a ridge that islocated on a ring that extends past the outside edge of the bone plate;

FIG. 2B shows a top-view of the bone-plate of FIG. 2A;

FIG. 3A shows a perspective view of a bone plate with a ridge that isinset from the outer edge of the plate;

FIG. 3B shows a top-view of the bone plate of FIG. 3A;

FIGS. 4A, 4B, and 4C show various views of a bone plate that isconstructed to receive optional bone spikes;

FIG. 5A shows a tool for inserting a spike into the plate shown in FIG.4A with the plunger in an extended position;

FIG. 5B shows a close-up view of the distal end of the tool of FIG. 5A;

FIG. 6A shows a tool for inserting a spike into the plate shown in FIG.4A with the plunger in a depressed position;

FIG. 6B shows a close-up view of the distal end of the tool of FIG. 6A;

FIG. 7 shows a bone screw with a notched head;

FIG. 8 shows a close-up view of the bone screw of FIG. 7;

FIG. 9A shows a side view of a bone plate with a set screw and anotched-head bone screw; and

FIG. 9B is a cutaway view taken along line B-B in FIG. 9A.

FIG. 10 shows a system including a tool for aligning a bone plate with aspacer body.

FIG. 11 shows an alternative system including a tool for aligning a boneplate with a spacer body.

FIG. 12 shows an additional alternative system including a tool foraligning a bone plate with a spacer body.

FIG. 13A shows an additional alternative system including a tool foraligning a bone plate with a spacer body.

FIG. 13B shows an alternative tool for aligning a bone plate with aspacer body.

FIG. 14 shows a spacer body.

FIG. 15A shows a top perspective view of a plate insertion device fordelivering a plate to a desired location adjacent the spine.

FIG. 15B shows a perspective view of a distal portion of the plateinsertion device of FIG. 15A grasping a plate.

FIG. 16A shows a top perspective view of an alternative plate insertiondevice for delivering a plate to a desired location adjacent the spine.

FIG. 16B shows a perspective view of a distal portion of the plateinsertion device of FIG. 16A grasping a plate.

FIG. 16C shows a bottom perspective view of a distal portion of theplate insertion device of FIG. 16A grasping a plate.

FIG. 16D shows a bottom perspective view of a distal portion of theplate insertion device of FIG. 16A grasping a plate at an alternativeangle.

DETAILED DESCRIPTION OF THE DISCLOSURE

The aspects of the disclosure and the various features and advantageousdetails thereof are explained more fully with reference to thenon-limiting aspects and examples that are described and/or illustratedin the accompanying drawings and detailed in the following description.It should be noted that the features illustrated in the drawings are notnecessarily drawn to scale, and features of one aspect may be employedwith other aspects as the skilled artisan would recognize, even if notexplicitly stated herein. Descriptions of well-known components andprocessing techniques may be omitted so as to not unnecessarily obscurethe aspects of the disclosure. The examples used herein are intendedmerely to facilitate an understanding of ways in which the disclosuremay be practiced and to further enable those of skill in the art topractice the aspects of the disclosure. Accordingly, the examples andaspects herein should not be construed as limiting the scope of thedisclosure, which is defined solely by the appended claims andapplicable law. Moreover, it is noted that like reference numeralsrepresent similar parts throughout the several views of the drawings.

The terms “including”, “comprising” and variations thereof, as used inthis disclosure, mean “including, but not limited to”, unless expresslyspecified otherwise.

The terms “a”, “an”, and “the”, as used in this disclosure, mean “one ormore”, unless expressly specified otherwise.

Although process steps, method steps, algorithms, or the like, may bedescribed in a sequential order, such processes, methods and algorithmsmay be configured to work in alternate orders. In other words, anysequence or order of steps that may be described does not necessarilyindicate a requirement that the steps be performed in that order. Thesteps of the processes, methods or algorithms described herein may beperformed in any order practical. Further, some steps may be performedsimultaneously.

When a single device or article is described herein, it will be readilyapparent that more than one device or article may be used in place of asingle device or article. Similarly, where more than one device orarticle is described herein, it will be readily apparent that a singledevice or article may be used in place of the more than one device orarticle. The functionality or the features of a device may bealternatively embodied by one or more other devices which are notexplicitly described as having such functionality or features.

An incision, which may be no more than, e.g., about two inches long, maybe made in a patient to perform a fusion of adjacent vertebrae. Allinstrumentation should pass through this incision, which naturallylimits the size of bone plates and other hardware that may be used inthe procedure. In certain situations, this size restriction can resultin the use of a plate with a suboptimal amount of bone screws. Screwsmay be omitted due to difficulties in inserting the screws and otherhardware through the incision. In other situations, the plate itself mayonly accept a suboptimal number of screws. Adding an optimal number ofholes may make the plate too big to fit through the incision orotherwise satisfy space restrictions. Other situations and circumstancesmay also limit the number of screws used to attach a bone plate.

FIGS. 1A-4C and 7 show various examples of a bone plate 100 (100A, 100B,100C, 100D, 100E) that may be implemented in spine fusion procedures toprovided added stability in, e.g., the afore-noted situations. The boneplate 100 includes side walls 107 (107A, 107B), a top surface 108 (108A,108B, 108C, 108D), and a bottom surface 109 (109A, 109B, 109C, 109D).The bone plate 100 may include one or more holes 101 that are configuredto receive respective one or more bone screws (such as, e.g., the bonescrew 300, shown in FIGS. 7-9B). The bone plate 100 may further includea central hole 104. The bone plate 100 may also include one or morereceivers 110 that are configured to receive respective one or more setscrews 102. The set screws 102 may help to retain the bone screws in thebone plate 100 and the bone (not shown), preventing the screws fromloosening.

Referring to FIGS. 1A-1B, the bone plate 100A may include a ridge 103Afor added stability. The wall(s) of the ridge 103A may be tapered. Theridge 103A may be formed along (or near) a perimeter of the bone plate100A. The ridge 103A may run along the entire perimeter of the boneplate 100A, or only a portion of the perimeter of the bone plate 100A.The bone plate 100A may be integrally formed with the ridge 103A. Inparticular, the bottom surface 109A of the bone plate 100A may beintegrally formed with the ridge 103A.

FIG. 1A shows a perspective view of the underside, or bottom surface109A, of the bone plate 100A, which is constructed with the ridge 103Abeing substantially flush with the side walls 107A of the bone plate100A. The walls of the ridge 103A are tapered to form a substantiallysharp edge along the perimeter of the ridge 103A.

FIG. 1B shows a view of the top surface 108A of the bone plate 100A. Theridge 103A is not visible in this top view, since the outer walls of theridge 103A are substantially flush with the side walls 107A of the boneplate 100A.

FIGS. 2A-2B show a bone plate 100B with a ring 105 and a ridge 103B,both of which may be integrally formed with the bone plate 100B. Theridge 103B may be formed on the ring 105, along the perimeter of thering 105. The ring 105 may extend beyond the walls 107A of the boneplate 100B. The ring 105 may also extend beyond the bottom surface 109Bof the bone plate 100B.

FIG. 2A shows a perspective view of the bottom surface 109B of the boneplate 100B, including the ridge 103B and the ring 105. As seen, theridge 103B may include an inner wall that is configured to taper fromthe bottom surface 109B of the bone plate 100B (or the bottom surface ofthe ring 105) to the edge (or end) of the ridge 103B. Further, the ridge103B may include an outer wall(s), which may be formed on the bottomsurface of the ring 105, or which may be formed as part of the outerwall of the ring 105. The ring 105 may include an outer wall that may besubstantially normal to the bottom surface 109B and substantiallyparallel to the walls 107A of the bone plate 100B. The outer wall of thering 105 may be angled so as to taper off to an edge (or end) with theinner wall of the ridge 103B.

FIG. 2B shows a view of the top surface 108B of the bone plate 100B,including the ring 105. As seen, the ring 105 may be visible from thetop view of the bone plate 100B.

FIGS. 3A-3B show a bone plate 100C with a ridge 103C that is formedinward of the perimeter of the bottom surface 109C. In particular, theridge 103C is formed in the bone plate 100C so as to be inset from walls107A of the bone plate 100C. One or both of the inner and outer walls ofthe ridge 103C may be tapered, so that wall(s) of ridge 103C taper offalong a normal (or perpendicular) path from the bottom surface 109C tothe edge (or end) of the ridge 103C.

FIG. 3A shows a perspective view of the bottom surface 109C, includingthe ridge 103C. As seen, the ridge 103C is inset from the walls 107A ofthe bone plate 100C.

FIG. 3B shows a view of the top surface 108C of the bone plate 100C. Inthis view, the ridge 103C is not visible.

While each of the figures shows only one ridge 103 (103A, 103B, 103C),those skilled in the art will recognize that multiple ridges 103 may beused without departing from the spirit or scope of the specification,including the attached claims. In particular, two or more ridges 103 maybe used. For example, the ridge 103A of FIG. 1A may be combined with theridge 103B of FIG. 2A to produce a bone plate 100 that includes a pairof ridges 103A, 103B (not shown). In addition, multiple ridges 103B maybe located on the ring 105 shown in FIGS. 2A and 2B. The above is not anexhaustive list of the possible or contemplated examples, and furtheraspects will be apparent to those skilled in the art.

The inner wall and/or the outer wall of the ridge 103 (103A, 103B, 103C)may be tapered to a sharp edge (or end). The ridge 103 may also have asubstantially sharp edge that is formed by substantially parallel innerand outer walls of the ridge 103 (not shown). Thus, by firmly attachinga bone plate 100 with a ridge 103 to, e.g., an underlying bone, using,e.g., a bone screw, the ridge 103 may contact and penetrate (or diginto) the bone. With the ridge 103 successfully implanted into the bone,lateral sliding of the bone plate 100 on the bone may be substantiallyor completed reduced or eliminated. The use of multiple ridges 103 mayfurther enhance the anti-sliding effect of the ridges 103.

In addition, the ridge 103 may strengthen the bone-plate interface inadditional ways. When the bone plate 100 is applied over multiplevertebrae, for example, the ridge 103 may work with the bone screws toprevent the vertebrae from moving relative to one another. Furthermore,the ridge 103 may be treated with a coating, such as, e.g.,hydroxyapatite coating, titanium plasma spray, to encourage bonyon-growth, which may stabilize or strengthen the interface between theplate and the underlying bone.

The improved stability imparted by a ridge 103 may have one or moreeffects on the use or design of the bone plate 100. As statedpreviously, the need for screws may be reduced. As a result, fewerscrews may be used to secure the bone plate 100 to a bone, withoutcompromising stability. Similarly, the size of the bone plate 100 may bereduced without a reduction in stability. A smaller bone plate 100 willlikely require a smaller incision, which in turn may cause less traumato the patient and improve recovery time.

According to a further aspect of the disclosure, the bone plate 100 mayinclude one or more sharp spikes to improve stability. The function ofthe spike is similar to that of the ridge 103 described above, but thespike may extend further away from the bone plate 100. FIGS. 4A, 4B, and4C show various views of the bone plate 100D. The bone plate 100D isconfigured to receive one or more spikes. In particular, the bone plate100D is configured to receive one or more optional spikes 206 that maybe inserted in and through one or more respective openings 106 (in thebone plate 100D) and into, e.g., the bone (not shown). Once the boneplate 100D is securely attached to the bone with bone screws (e.g., thebone screws 300, shown in FIG. 7), one or more optional spikes 206 maybe inserted through the spike holes 106 with a special tool 200 (shownin FIGS. 5A-6B).

Referring to FIGS. 5A-6B, the tool 200 includes a body 201, a plunger202, and a shaft 203. The shaft 203 may run through the center and alongthe length of the body 201 and connect to the plunger 202 at a proximalend of the tool 200. The tool 200 is configured so that when the plunger202 is depressed by, e.g., a surgeon, the shaft 203 is caused to moveand extend from the distal end of the tool 200. Likewise, when theplunger 202 is in an extended position, the shaft 203 may be retractedfrom the distal end of the tool 200 by, e.g., a pulling force.

At the distal end of the tool 200, the shaft 203 may pass through a ring204, which may act as a base for two or more panels 205. The distal endof the tool 200 may also be provided with slits. The interior of thepanels 205 and the distal end of the shaft 203 may be designed in such away that they close together, forming a continuous shape, when theplunger 202 is in a retracted position (i.e. when the plunger 202 isextended, shown in FIG. 5A). In addition, depressing the plunger 202 andextending the shaft 203 may cause the panels 205 to separate, as shownin FIG. 6B. For example, the distal end of the shaft 203 may have atapered shape that presses against the interior walls of the panels 205as the shaft 203 is extended.

The panels 205, the distal end of the shaft 203, or both may beconfigured to retain an optional spike 206 for use with the bone plate100D shown in FIGS. 4A-4C. For example, the shaft 203 may be magnetized.In this instance, the shaft 203 may be used to pick up and easily retaina spike 206 that is manufactured from a ferromagnetic material. Thepanels 205 may contain an interior notch or ridge for gripping the spike206 when the panels 205 are in a closed position. In addition, thepanels 205 may be biased by a spring or other mechanism (not shown),enabling the panels 205 to grip the spike 206 with considerable force.

FIG. 5A shows the spike tool 200 with the plunger 202 in an extendedposition. The distal end of the shaft 203 is retracted and the panels205 are closed. The panels 205 are holding a spike 206 for use with thebone plate 100D shown in FIGS. 4A-40. FIG. 5B provides a magnified viewof the distal end of the tool 200, which shows an example of how thepanels 205 may come together.

A tool 200 in this configuration may be used to insert a spike 206through a spike hole 106 of the bone plate 100D. The hole 106 may beconfigured to mechanically engage and retain the spike 206 after it haspassed a certain point. For example, the hole 106 may include a beveledridge or ridges that allows the spike 206 to pass the ridge as it isinserted, yet prevents the spike 206 from working free of the hole 106.Additionally or alternatively, the hole 106 may include a ridge or notchthat serves as a lower limit for the spike 206. In this instance, thespike may be prevented from being inserted through this ridge or notch.The limit ridge and the beveled ridge may work together to substantiallyfix the spike 206 in place, maximizing the spike's 206 contribution tothe stability of the bone-plate interface and the overall construct.

FIG. 6A shows the tool 200 with the plunger 202 depressed and the shaft203 extended. FIG. 6B shows a close-up of the distal end of the tool200. Shaft 203 may force apart or separate the panels 205 while the tool200 still retains the spike 206.

A bone plate 100D with optional spikes eliminates sharp protrusions fromthe plate that may injure blood vessels, nerves, and other anatomicalfeatures. In addition, the bone plate 100D may be used without some orall of the optional spikes 206 being inserted. This may allow surgeonsor hospitals to reduce the number and type of bone plates 100 they keepin stock, thereby reducing costs.

FIG. 7 shows an example of a bone screw 300 that is constructedaccording to the principles of the disclosure. The bone screw 300 mayinclude a notched head. The bone screw 300 may be used with a bone plate100E. The bone plate 100E may be configured as any one of the boneplates 100A-100D previously described. The bone screw 300 may be usedwith a set screw 102 to prevent the bone screw 300 from working out ofthe underlying bone (not shown). As seen in FIG. 7, the bone plate 100Emay include a hole 101 for receiving the bone screw 300 and a receiver110 (such as, e.g., a hole) for receiving the set screw 102.

FIG. 8 provides a close-up view of the head portion of the bone screw300. The head portion of the bone screw 300 may include alternatingridges 302 and notches 303. This arrangement allows the set screw 102 tophysically engage the head of the bone screw 300, thereby preventingboth rotation and backing out of the bone screw 300 from the bone or thebone plate 100E. The bone screw 300 may also include bone threads 304,which are configured to penetrate and engage, e.g., bone.

FIG. 9A shows a side view of the plate 100E with a set screw 102 andbone screw 300. FIG. 9B is a cutaway view taken along line B-B. FIG. 9Bshows how the set screw 102 may interface with the ridges 302 andnotches 303 of the head portion of the bone screw 300. This interactionmay substantially or completely prevent rotation of the bone screw 300when the construct, including bone plate 100E, is subjected to normalbiomechanical forces within the body.

Various systems, devices and methods for aligning a plate with a spacerbody are now provided. While the systems, devices and methods aredescribed with respect to a plate 100 having ridged features asdiscussed above, they are not limited to this particular type of plate,and can be used to align various other types of plates with a spacerbody.

FIGS. 10-12 show various systems that allow a plate 100 to be guided andaligned with a spacer body 10. In some embodiments, a spacer body 10 isalready inserted and positioned at a location within a spine. Thesystems described herein provide a convenient means to guide a plate 100through a small incision path toward the spacer body 10. Advantageously,the plate 100 can be guided through an incision and a small opening(e.g., formed by a retractor), until it is positioned and fixed adjacentthe spacer body 10

FIG. 10 shows a system including a tool for aligning a bone plate with aspacer body. The system includes a spacer body 10, a bone plate 100having fasteners 300, and a guide 400 for aligning the bone plate withthe spacer body. An optional keying tool 500 is also provided to assistin preventing rotation of the plate 100 with respect to the spacer body10, as discussed further below.

The spacer body 10 includes a superior surface 22 and an inferiorsurface 26 that are configured to contact upper and lower vertebrae,respectively. In some embodiments, the surfaces can include surfaceprotrusions, such as teeth or ridges, to assist in gripping the surfacesof the vertebrae. An opening 15 can be formed through the spacer body.The opening 15 can be configured to receive bone material, such as bonegraft material, to facilitate fusion of the spacer body 10 within thevertebrae. In some embodiments, the opening 15 is substantiallyrectangular in shape, while in other embodiments, the opening 15 is morecircular.

In some embodiments, the spacer body 10 can also include a recess 32formed on an anterior and/or posterior face. As shown in FIG. 14, therecess 32 can be circular, rectangular or various other configurations.The recess 32 can transition into an aperture 36 that is smooth orthreaded. In some embodiments, the aperture 36 is configured to receivea portion of a guide member 400, as discussed in more detail below.

The spacer body 10 can be inserted in between two vertebrae. Once thespacer body 10 is inserted in a desired position, a bone plate 100 canbe provided through an incision and can be placed adjacent the spacerbody 10.

The bone plate 100 can include any of the features discussed above,including one or more holes 101 for receiving fasteners 300 and anadditional central hole 104 for receiving a guide 400. The bone plate100 can also include a ridged perimeter. In some embodiments, the boneplate 100 is configured to be placed adjacent to the spacer body 10,such that it can be fixed to upper and lower vertebrae via fasteners300. While in some embodiments, the bone plate 100 is attached to thespacer body 10, in other embodiments, the bone plate 100 is not attachedto the spacer body 10. As shown in FIG. 10, in some embodiments, thebone plate 100 is placed perpendicularly at about a 90-degree anglerelative to the spacer body 10. In other embodiments, the bone plate 100can be placed at a different angle from 90-degrees relative to thespacer body 10. In order to place the bone plate 100 in a desiredposition, the system includes a unique guide 400 that can guide the boneplate 100 through an incision path.

The novel guide 400 can include a first substantially rigid portion 402and a second more flexible portion 408. In some embodiments, the rigidportion 402 can be of a different material from the flexible portion408. For example, in some embodiments, the rigid portion 402 cancomprise a metal such as stainless steel that is operably attached to aflexible portion 408 comprising a nitinol wire. The stainless steelrigid portion 402 can advantageously comprise a threaded portion 414(shown in FIG. 10) that allows the guide 400 to be attached to thespacer body 10. In some embodiments, the rigid portion 402 comprises amaterial other than stainless steel, such as PEEK, cobalt chrome,nitinol, TAV, CP (titanium) or other compatible biomaterial.

The flexible portion 408 of the guide 400 can extend outwardly from therigid portion 402 and outwardly from an incision. When the flexibleportion 408 extends outwardly from the incision, a plate 100 can bedelivered down the flexible portion. In some embodiments, the flexibleportion 408 advantageously allows a plate 100 to be inserted at anon-perpendicular angle to retractor blades, thereby decreasing the sizeof the aperture needed to insert the plate therethrough. In someembodiments, the flexible portion 408 is fastened into the rigid portion402. In some embodiments, an epoxy filler can be used to secure theflexible portion 408 to the rigid portion 402. The flexible portion 408can be comprised of various materials, including but not limited tonitinol. In addition, in some embodiments, the flexible portion 408 cancomprise a stainless steel or titanium cable.

Together, the flexible portion 408 and rigid portion 402 can be viewedeither as a single guide member, or as multiple guide members securedtogether. In some embodiments, the length of the rigid portion 402 canbe between about 2 and 25 percent, or between about 5 and 10 percent, ofthe length of the entire guide 400 having a flexible portion 408 and arigid portion 402 In some embodiments, the length of the rigid portion402 can be between about 15 and 45 mm, or about 30 mm. The length of theflexible portion 408 can be between about 350 and 550 mm, or about 450mm. In some embodiments, the rigid portion is just long enough to engagea plate 100 when it is seated on the vertebral bodies and just longenough for a tool to connect to it to insert it and remove it after theplate 100 has been placed Advantageously, these dimensions allow theflexible portion 408 to extend outwardly from an incision, whilemaintaining the rigid portion 402 near the inserted spacer body 10.

In operation, after the spacer body 10 has been inserted into a desireddisc space, the guide 400 can be attached to the spacer body 10. Thebone plate 100 can be inserted over the guide 400 via the central hole104, where it can travel over the flexible portion 408 and subsequently,over the rigid portion 402 of the guide 400. In some embodiments, thecentral hole 104 can be non-circular (e.g., square or rectangular)and/or with edges, thereby advantageously minimizing rotation of theplate 100 as it travels along the guide 400. Advantageously, while thebone plate 100 is delivered over the flexible portion 408, the boneplate 100 is capable of assuming a number of different orientations viatilting and manipulation, thereby allowing a minimally invasive delivery(e.g., through retracted tissue). After passing the flexible portion 408of the guide 400, the plate 100 traverses over the rigid portion 402 ofthe guide 400. The rigid portion 402 of the guide 400 advantageouslyhelps to align the plate 100 with the spacer body 10. Once the plate 100is in place adjacent the spacer body 10, it can be secured to vertebraevia fasteners 300.

Optionally, a keying tool 500 (shown in FIG. 10) can be provided toassist in preventing rotation of the plate 100 with respect to thespacer body 10. The keying tool 500 comprises a sleeve that isconfigured to slide over the guide 400 and through the central hole 104.In some embodiments, the keying tool is made of a biocompatible metal,such stainless steel or titanium. In some embodiments, the keying tool500 can have a shape that corresponds to the shape of the central hole104 and/or the shape of the recess 32 in the spacer body 10. By having acorresponding shape, this advantageously prevents rotation of the plate100 relative to the spacer body 10. In some embodiments, the keying tool500 can have a non-circular shape and/or shape with edges thatcorresponds with the shape of the central hole 104. In some embodiments,the keying tool 500 is slightly smaller than the central hole 104 of theplate 100, thereby advantageously allowing for a minimal amount oftoggle and misalignment of the parts. While the keying tool 500 is shownwith respect to the system in FIG. 10, it can also be used with thesystems shown in other embodiments. In addition, when the keying tool500 is not inserted into a recessed area of the spacer, it can be usedto rotate the plate to any angle desired. In an alternative embodiment,the keying tool 500 can be made cylindrical to take up slop between therigid portion of the guide 400 and the plate 100, but still allow theplate 100 to be rotated thereon.

FIG. 11 shows an alternative system including a tool for aligning a boneplate with a spacer body. Like the system in FIG. 10, the present systemincludes a spacer body 10, a plate 100 and a guide 400 having a flexibleportion 408 and a rigid portion 402. However, rather than having a screwmember 414 attached to the rigid portion 402, the present guide 400 hasa rigid portion 402 including a pressure press-fit end 419 that holdswithin the spacer body 10. The shape of the pressure press-fit end 419advantageously correlates to the shape of the plate recess 32 (shown inFIG. 14) such that when the plate 10 is slid over the rigid portion 402of the guide 400, it is guided and keyed into a proper position. Theplate 100 is thus held in line with the spacer body 10.

In some embodiments, the recess 32 of the spacer body 10 can be shapedand dimensioned to allow movement of the press-fit end 419. For example,the recess 32 can have a slightly larger length than the press-fit end419 of the guide 400, thereby allowing some side translation of theguide 400. The guide 400 can thus be translated off-center, therebyallowing both center and off-center placement of the plate 100 relativeto the spacer body 10. This advantageously allows a surgeon to place theplate 100 in various locations relative to the spacer body 10.

FIG. 12 shows an additional alternative system including a tool foraligning a bone plate with a spacer body. The system comprises a spacerbody 10, a plate 100 and an alternative keying tool 600 having adistinct design.

Once the plate 100 has been positioned adjacent the spacer body 10(e.g., via a guide 400 as discussed above), a keying tool 600 can beprovided. In some embodiments, the keying tool 600 is provided on itsown, while in other embodiments, the keying tool 600 is cannulated andextends over the guide to a desired surgical location. In someembodiments, the keying tool 600 can comprise a fork-member having oneor more fingers, prongs or tines to assist in holding the position ofthe plate 100 relative to the spacer body 10. One or more of the prongscan have a shape (e.g., non-circular) that corresponds with the shape ofthe central hole 104. As shown in FIG. 12, the keying tool 600 cancomprise at least two prongs 602 and 604. First prong 602 extendsthrough a central hole 104 of the plate 100 and into the recess 32 ofthe of the spacer body 100. Advantageously, the shape of the first prong602 substantially correlates with the shape of the central hole 104 ofthe plate in order to properly align the plate and/or prevent it fromrotating. Second prong 604 is parallel and off-set axially from firstprong 602, and can also extend into the recess 32 of the spacer body ifdesired. In some embodiments, the first prong 602 and the second prong604 are of different lengths such that one prong can extend into therecess 32 of the spacer body, while the other does not extend into therecess 32 of the spacer body. In addition, in some embodiments, thespacer body recess 32 is dimensioned to allow translation of the keyingtool 600 therein.

FIG. 13A shows an additional alternative system including a tool foraligning a bone plate with a spacer body. Like the system in FIG. 12,the present system includes a spacer body 10, a plate 100 and a keyingtool 600. However, the keying tool 600 in FIG. 13A includes three prongs602, 604 and 606. First prong 602 extends through the central hole 104of the plate 100 and into the recess 32 of the spacer body 10. The shapeof the first prong 602 substantially correlates with the shape of thecentral hole 104 of the plate 100 so that it is advantageously preventedfrom rotating relative to the spacer body 10. Second prong 604 and thirdprong 606 extend parallel to the first prong 602. In some embodiments,as shown in FIG. 13A, the second prong 604 and third prong 606 can restagainst the outside surface of the spacer body 10, therebyadvantageously providing additional stabilization to the system. In someembodiments, sides of the spacer body 10 can include recessed slots thatcan allow one or more of the prongs (e.g., prongs 604, 606) to slideinto therein, thereby further helping to stabilize the position of theplate relative to the spacer.

FIG. 13B shows an additional alternative tool for aligning a bone platewith a spacer body. The keying tool 600 includes two prongs 602 and 604.In some embodiments, the first prong 602 can be received through acentral hole of the plate 100, while the second prong 604 can extendalong a side of the plate 100 and/or spacer 10. As shown in FIG. 13B,the two prongs can have different lengths.

Any of the keying tools shown in FIGS. 10, 12, 13A and 13B can becannulated to slide over the surface of the guide comprising the rigidand flexible members. In some embodiments, the cannulated portion of thekeying tools is large enough to accept additional tools other than theguide.

Various methods are provided for inserting the systems described above.In some embodiments, a surgeon will form an incision and a path to adisc space. A spacer body, such as one with a ridged perimeter, can bedelivered and inserted into the disc space. A guide, such as one havinga rigid portion and a flexible portion, can be delivered and operablyconnected to the spacer body. A plate can then be delivered over theguide, first over the flexible portion and then over the rigid portion.Once the plate is delivered to a desired area adjacent the spacer body,the plate can secured to vertebrae using one or more fasteners.Optionally, before and/or after securing one or more fasteners of theplate into a vertebral body, a keying tool can be provided. In someembodiments, the keying tool comprises a cannula that fits over theguide and through a central hole in the plate. The keying tooladvantageously helps to prevent rotation of the plate relative to thespacer body prior to securing the system. Once the spacer body and plateare secured (or temporarily held in place by temporary fixation pins),the guide and/or keying tool can be removed.

To assist in delivering a plate to a location adjacent a spine,different insertion devices can be provided as discussed herein. Thesenovel insertion devices advantageously afford a surgeon an effectiveinstrument for delivering the plates while maintaining a slim profile toallow surgeons to see a surgical site.

FIG. 15A shows a top perspective view of a plate insertion device fordelivering a plate to a desired location adjacent the spine. FIG. 15Bshows a perspective view of a distal portion of the plate insertiondevice of FIG. 15A grasping a plate.

The plate insertion device 300 comprises a number of componentsincluding a sleeve 320 extending to a proximal portion 340 of the devicethat serves as a handle. A grasping member 310 for securely holding aplate 100 extends from a distal opening of the sleeve 320. The graspingmember 310 comprises a pair of parallel jaws 311. Hinged tips 312 havingextension portions 314 extend from the parallel jaws 311.

The grasping member 310 of the device 300 comprises a pair of paralleljaws 311. The parallel jaws 311 can be configured to contract andexpand. In some embodiments, when the parallel jaws 311 are in acontracted configuration, the jaws 311 can be slid into the body of thesleeve 320. In some embodiments, when the parallel jaws 311 are in anexpanded configuration, the jaws 311 extend outward from the body of thesleeve 320. The parallel jaws 311 can be spring-loaded. In someembodiments, the parallel jaws 311 are configured to hold a side of aplate 100 (as shown in FIG. 15B). In other embodiments, the paralleljaws 311 can hold posterior and/or anterior surfaces, or upper and lowersurfaces of the plate 100.

Hinged tips 312 are connected to the parallel jaws 311. The hinged tips312 comprise curved fingers that can rotate and/or actuate around one ormore pivot pins 313 (shown in FIG. 15B). In some embodiments, rotationof the hinged tips 312 can be controlled by an actuation member. Thehinged tips 312 are advantageously configured to pivot and allow a largerange of rotation in a very small arc, such that the device 300 can bedelivered with a plate 100 through a very small opening. Advantageously,the arms of the hinged tips 312 are offset from the pivot point, therebyallowing the use of center hole in the plate 100. Moreover, the hingedtips 312 advantageously provide a surgeon with flexibility in placingthe plate 100 in a desired location. In some embodiments, the hingedtips 312 are able to hold a plate 100 about or completely perpendicularto the instrument (e.g., the longitudinal axis of the sleeve 320) androtate it up to the point that it is almost parallel to the sleeve 320.A stop formed on the hinged tips 312 can assist in prevent over-rotationof the plate. By providing such a rotational feature, thisadvantageously makes it easier to cause the plate 100 to begin rotatingwhen inserting it and pushing it against the surface of a vertebral bodyin some instances.

Extension portions 314 extend inwardly (e.g., to face a mid-line of thedevice 300) from the hinged tips 312. These extension portions 314 areadvantageously configured to securely grip a recess formed in the bodyof the plate 100, as shown in FIG. 15B.

The parallel jaws 311 and hinged tips 312 are configured to encompass anopening 318 in the grasping member 310. Advantageously, when a plate 100is secured to grasping member 310 (as shown in FIG. 15B), the opening318 in the grasping member 310 provides a means to visualize the plate100. In addition, in some embodiments, the opening 318 in the graspingmember 310 can be substantially aligned with the central hole 104 of theplate 100. In this situation, when the opening 318 is aligned with thecentral hole 104 such that the opening 318 is in front of thecross-member between the tips 312, this advantageously allows the plate100 to be inserted over a flexible guide while it is being held by theplate insertion device 300. As the grasping member 310 holds the plate100 via recesses on its side body, the central hole 104 can remain inuse such that a guide (such as the combined flexible and rigid guidediscussed above) can still be used through the central hole 104. Thus,the plate insertion device 300 can advantageously be used with a guidethat extends through the hole 104 of the plate 100.

The grasping member 310 can extend outwardly from an opening in thesleeve 320. In some embodiments, the sleeve 320 extends a majority ofthe length of the device 300. The sleeve 320 can include a narrowmid-section that becomes slightly wider near its proximal end to form aproximal handle portion 340. The slim design of the sleeve 320 and itshandle proximal handle portion 320 advantageously helps to maintain thesightlines of the surgeon through the use of the instrument. In someembodiments, the diameter of the sleeve 320 is between about 5 and 15mm, or between about 8 and 12 mm The most proximal end of the sleeve 320can be in contact with an actuation knob 342, which can be configured toopen and close the arms of the grasping member 310. In some embodiments,the actuation knob 310 can be connected to the parallel jaws 311 via aninternal rod with a threaded end. When the knob 310 is turned, it pullsor pushes the jaws into or out of the sleeve 320, thereby causingexpansion or contraction.

In some embodiments, the actuating knob 342 can have external surfaceroughening, such as ribbing, a knurled surface, etc. so as to beconveniently gripped by a surgeon. In some embodiments, rotating theactuating knob 342 closes the parallel jaws 311 such that they securelygrip a surface of the plate 100. Rotating the actuating knob 342 in anopposite direction will open the parallel jaws 311 to release the plate100 therefrom. As the actuating knob 342 is controlled by a smoothcontrolled rotation, the parallel jaws 311 can open or close in acontinuous manner, thereby gripping or releasing the plate 100 in anaccurate, controlled manner. In some embodiments, the parallel jaws 311are advantageously spring-loaded to provide a secure grip on the plate100. In this situation, the spring can act to open the parallel jaws andthe sleeve can act to close the parallel jaws as they are pulled intothe sleeve

FIGS. 16A-D show different views of an alternative plate insertiondevice for delivering a plate to a desired location adjacent the spine.The device 400 includes a sleeve 420 and a grasping member 410 thatextends from an opening of the sleeve 420. A distal portion of thegrasping member 410 includes an articulating linking member 413configured to rotate and articulate distal extension arms 412. Theextension arms 412 include outward protrusions 414 that help to secure aplate 100, as shown in FIGS. 16B and 16C.

Unlike the grasping member 310 in FIG. 15A, the grasping member 410 inFIG. 16A is configured to attach to the central hole 104 in the plate100 if desired. One skilled in the art will appreciate that holes otherthan the central hole 104 of the plate 100 can also be used forattachment by grasping member 410. In some embodiments, the graspingmember 410 includes an articulating linking member 413 that is capableof articulating and rotating distal extension arms 412 (e.g., between 0and 90 degrees). Articulation of the linking member 413 can be performedvia rotation of a knob, such as the one shown on the proximal portion ofthe device 300 in FIG. 15A. When the linking member 413 is rotated, thisalso rotates arms 412. The arms 412 can be attached to the plate viaprotrusions 414 that extend outwardly (e.g., away from a midline of thedevice 400) from the arms 412.

Advantageously, as the grasping member 410 of the device 400 includesarms 412 that are capable of gripping a central hole of the plate 100 ofminimal diameter, the device 400 is extremely small in width and thuscapable of being used through very small incisions. After enteringthrough a small incision, the device 400 advantageously provides theability to control the articulation of the plate 100 in a verycontrolled manner.

It will be apparent to one skilled in the relevant arts that any of theabove-described modifications may be combined. For example, a bone platemay include a sharp, peripheral ridge to enhance stability of theconstruct; optional spikes for further enhancing stability; andnotched-head bone screws to prevent rotation of the screws inside thebody. Other combinations are possible and contemplated. A bone plate orother construct or instrumentation may utilize any combination of theabove-described enhancements without departing from the spirit and scopeof the specification, including the attached claims.

While the disclosure has been described in terms of exemplary aspects,those skilled in the art will recognize that the disclosure can bepracticed with modifications in the spirit and scope of the appendedclaims. These examples given above are merely illustrative and are notmeant to be an exhaustive list of all possible designs, aspects,applications or modifications of the disclosure.

What is claimed is:
 1. A surgical system comprising: a spacer body; abone plate attachable to the spacer body; a tool for aligning the boneplate to the spacer body.
 2. The surgical system of claim 1, wherein thespacer body comprises a superior surface and an inferior surface, and anopening that extends through the superior surface and inferior surface.3. The surgical system of claim 2, wherein the spacer body furthercomprises an anterior surface and a posterior surface between thesuperior surface and inferior surface, wherein the anterior surfacecomprises a recess.
 4. The surgical system of claim 3, wherein therecess in the anterior surface of the spacer body transitions into asmaller opening therein.
 5. The surgical system of claim 3, wherein thebone plate comprises an upper fastener and a lower fastener extendingtherethrough.
 6. The surgical system of claim 1, wherein the tool foraligning the bone plate comprises a guide.
 7. The surgical system ofclaim 6, wherein the guide comprises a rigid portion and a flexibleportion.
 8. The surgical system of claim 7, wherein the rigid portioncomprise a metal and the flexible portion comprises nitinol wire.
 9. Thesurgical system of claim 7, wherein the flexible portion is fastenedinto the rigid portion.
 10. The surgical system of claim 1, furthercomprising a retractor for maintaining an incision opening in which thetool extends therethrough.
 11. A surgical system comprising: a spacerbody; a bone plate attachable to the spacer body, wherein the bone platecomprises a first hole for receiving a first bone fastener and a secondhole for receiving a second bone fastener and a central hole forreceiving a portion of a tool for aligning the bone plate to the spacerbody; a tool for aligning the bone plate to the spacer body.
 12. Thesurgical system of claim 11, wherein the spacer body comprises asuperior surface and an inferior surface, and an opening that extendsthrough the superior surface and inferior surface.
 13. The surgicalsystem of claim 12, wherein the spacer body further comprises ananterior surface and a posterior surface between the superior surfaceand inferior surface, wherein the anterior surface comprises a recess.14. The surgical system of claim 13, wherein the recess in the anteriorsurface of the spacer body transitions into a smaller opening therein.15. The surgical system of claim 13, wherein the bone plate comprises anupper fastener and a lower fastener extending therethrough.
 16. Thesurgical system of claim 11, wherein the tool for aligning the boneplate comprises a guide.
 17. The surgical system of claim 16, whereinthe guide comprises a rigid portion and a flexible portion.
 18. Thesurgical system of claim 17, wherein the rigid portion comprise a metaland the flexible portion comprises nitinol wire.
 19. The surgical systemof claim 17, wherein the flexible portion is fastened into the rigidportion.
 20. The surgical system of claim 11, further comprising aretractor for maintaining an incision opening in which the tool extendstherethrough.